As is well known, a thermistor is often used as an element body that detects temperature in a temperature sensor. As a temperature sensor for applications requiring various kinds of resistance properties such as oil resistance, chemical resistance, heat resistance, and cold resistance with respect to ambient environment in which a temperature detection object is placed, a temperature sensor in which a thermistor is sealed inside a coating layer made of a resin is used. For example, a patent literature 1 proposes a thermistor temperature sensor in which a thermistor element is connected to lead wires. In the proposed thermistor temperature sensor, the thermistor element and connection parts at which the thermistor element is connected to the lead wires are coated with an insulation tube through shrinkage in an insulation manner, and the outer side thereof is elastically coated with a coating tube.
According to the proposition of the patent literature 1, it is possible to manufacture the temperature sensor only by covering, with the insulation tube and the coating tube, the thermistor element and the connection parts at which the thermistor element and the lead wires are connected. This makes it possible to simplify the manufacturing operation of the temperature sensor to reduce manufacturing cost. In addition, a commercially-available tube can be used as the insulation tube and the coating tube, which also makes it possible to reduce manufacturing cost.